Question

Someone please actually help me with this. The lighthouse and the boat shown below

are 25.2 km apart.
The boat is 14.5 km east of the lighthouse.
Work out the bearing of the lighthouse from
the boat.
Give your answer to the nearest degree.

Answer 1

bearing ≈ 215°

Explanation:

the bearing of the lighthouse from the boat is the angle from the north line at the boat measured clockwise to the lighthouse.

calculate the angle inside the triangle at the boat

using the cosine ratio in the right triangle

cos B =
`(adjacent)/(hypotenuse)` =
`(14.5)/(25.2)` , then

∠ B =
`cos^(-1)` (
`(14.5)/(25.2)` ) ≈ 55° ( to the nearest degree )

the angle between North and West in clockwise direction = 270° , then

bearing = 270° - 55° = 215°